hoover



H. EL HOVW.

FIBER BEM'I'MG.` APPLICATION FILED MA". v l. 1918.

2 sHEETssHEET 1.

@m9, mmm De@ 2351919..

H. E. HOOVER.

FIBER BEARING.

APPLICAUUN 1115011111111, 19111.l

APatented Dee. 23,1919.

` 2 SHEETS-SHEET 2.

hll

HOWD EARL HOOVER, OF CHICAGO, ILLINOS, ASSIGNOR .lO THE HOOVER SUCTION SWEEPER COMPANY, OF NEW BERIIN, OIFHO, .ft CORPORATION OF OlO.

Specification of Lettera Patent. Patented mpg, 23, tgt@ Application filed Mulch lll, 19m. Seralll'o. gl.

To all whom it may concern:

Be it known that l, HOWARUEARL Hoeven, a citizen ofthe United States, residing at Chicago, in the county of Cook and State of lllinois, have invented a certain new and useful lmprovement in lFiher Bearings, of which the following is a specification.

My invention relates to improvements in and process of fitting hearings, and has particular relation to the small size high speed so called oilless hearings made of liber, wood or similar lubricant impregnated material.

4Une common use for such hearings, and ll have illustrated my invention in connection with such a device, is for the hrush in a suction sweeper, though oloviously these hearings might he used and are used in many different circumstances.

Experience has shown that with these small fiber or wood hearings they are ordinarily first forced hy pressure, into a hole or socket provided for them. "lhey are then at once or later reamed out to proper size so that the shaft passing through them may turn freely. Experience shows that when these hearings are allowed to stand for a while hefore heing reamed out they mature and if they are reamed out some months after they are pressed into place they remain properl sized and rotate freely on the shaft hut if tliey are first pressed in and then soon reamed .out to proper size, experience shows that after a month or so they will no longer he vthe proper size and will not rotate freely on the shaft. rllhe reason for this obviouslyl is that the more or less important distortion and compression of the hhrous material caused hy forcing the small cylindrical hearing sleeve into its seat sets up stresses in the material which only gradually adjust themselves, and thus a hearing which once was properly sized hefore this adjustment takes place is changed in size and shape during the progress of this adjustment. Ohviously it is not practical to hold a large numher of hearings waiting for this adjustment to take place, and so means must he provided for making this unnecessary.

One reason why the hearings are loclzed on the shaft hy the contraction of the hearing due to the readjustment of the internal stresses is that there must he a tight ht hetween the hearing and shaft toprevent rattle particularly so when there is an intermittent or pulsating load on the bearings as in the case/of a heatingbrush for a suction sweeper. Therefore, it will he seen that only a slight contraction will suce to prevent a grpat deal of rouhle.

accomp is m ur ose h so arran in@P the oilless hearing leepve and* the. surfceks of contact hetween it and the shaft' and it and the soclret in which it is mounted that these two contact surfaces are nowhere cut hy the same radius, that is to say, where the hearing sleeve is in contact with the shaft it is not in contact with the socket and vice versa and in order to make sure that the ihers will have ample room to hend or change in shape or position there is a short distance measured along the anis of the shaft between the two parallel planes terminating the ends of the contact surfaces of the hearing sleeve with the pocket and with the shaft.

ln one form ll slightly reduce the outer diameter of the hearing hoth inside and out ,so that the hearing does not engage the shaft throughout its entire length, and does not engage the seat or pocket throughout its entire length. ll may turn down the outside of the hearing cylinder for the larger part of its length leaving the shoulder at one end which engages the seat or l ma counter- 'lli sink the pocket which contains t e hearing so as to leave aplain cylindrical hearing in contact with the pocket only where reduced or l may turn down the central portiony of the outside of the hearing leavinoa shoulder at each endadapted to engage t e inside of l the pocket or seat. But in any event, ll so arrange the contact surfaces that where the hearing is in contact with the pocket it is not in contact with the shaft and vice versa. Or where a long hearing sleeve is used, l might have a plurality of ribs inside and out so that the shaft and the pocket would he engaged at a numher of di'erent points hut still always at diderent positions along the axis of the hearing. One form that would seem to he very desirahle where a comparatively long hearineP is used would he one in which the central inner portion of the hearing was cut away so that the hearing is in engagement with the shaft only at the ends hut is clamped'into the seat hy an enlarged part at the center leaving the ends of the sleeve reduced or at least out of Contact with the poclret containing them.

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No matter what the arrangement in its detail and obviously many other arrangements might be employed the resultv is that a bearing once forced into position may be trued up reamed out and put away with full knowledge no matter how long it stands, no matter how great its distortion within reason or`how much ripening takes place, still the bearing will turn freely on the shaft when put in use.

My invention is illustrated more or less diagrammatically in the accompanying drawings wherein- Figure 1 is a section of one form of the suction sweeper brush with bearing in place;

Fig. 2 is a perspective view of the device of Fig. 1;

Fig. 3 is a section Ashowing a modified form;

Fig. 4 is a further modification;

Fig. 5 is similar to Fig. 4 except that the arrangement of the inside and outside of the sleeve are reversed;

Fig. 6 is a further modification;

Fig. 7 shows a further modified form.

Like parts are indicated by like letters in all the figures.

A is a shaft upon'whieh the bearing is to be rotatabl mounted. This shaft maybe supported y any suitable means not here illustrated. I have shown rotating on this shaft a-brush body B. Obviously this particular kind of bearing need not be limited to use in connection with a suction sweeper brush but for the sake of showing some use, I have so illustrated it. The shaft B has projecting outwardlytherefrom a series of bristle bunches which in this case act as beaters so that the load on the bearings is intermittent being heavy when beating is taking place and light when the bristles are out of contact with the work. The shaft has enlarged ends D containing sockets E larger than the shaft.4 The socket is substantially concentric with the brush body and contains the cylindrical oilless wood bearing sleeve F. This bearing sleeve is turned down on its outside throughout most of its 'length as at Gr, but is left full size at I-I t0. engage the .wall ofthe poeketE so that when it is forced into place it engages the pocket only at the inner end where it is full size and is slightly out of engagement with the pocket with the supporting seat formed in the wall thereof throughout the major part of its length.

The inside of the bearing at I is bored out larger than the remainder. This part of the inner diameter is substantially in register 4with the part on the outside o-f larger diameter engaging the seat. The remainderv In Fig. 3 the outside of the bearing sleeve K is cyllndrical throughout its entire length and the end of the hollow shaft is eut away or counterbored so that the end of the bearing sleeve iits in, the remainder of the sleeve being out of contact with the wall of the pocket. Thus this portion of the pocket merely acts as a shield for the sleeve. It might be cut ofi' and the sleeve operated in exactly the same way being supported only at its end in the hollow shaft.

In Fig. 4 the bearing sleeve L is bored at each end as at L1 and reduced on the outside between the ends as at L2 and in F ig. 5 this is just reversed and the sleeve L3 is turned down at its ends on the outside and bored out intermediate its ends on the inside.

In Fig. 6 the sleeve M is bored out at each end and also intermediate the ends and turned down at two places on the outside intermediate its ends. It will be noted particularly in the later form where the bearing sleeve contacts the pocket in which it is contained at a number of different places that only a very short length of sleeve need be disposed in contact with the containing pocket because with the point of contact widely separated the turning moment is effectively resisted and a very large part of the sleeve can be used as bearing surface.

It will be noted above that I have shown the bearing sleeve in a pocket or socket in the en d of the hollow rotating shaft. Obviously lin connection with man3y kinds of machinery the pocket or socket would be in some fixed abutment and the shaft would be rotated but this would be the only change involved and the arrangement of parts would be exactly the same no matter for what kind of machinery the bearing was being used.

I have shown also the bearing locked in place by a set screw which set screw exerts a pressure on the bearing that might otherwise cause it to bind on the shaft were it not for the fact that the bearing is adjacent the shaft eut away so as to prevent any direct transmission of force from the set screw itself directly through the distorted fibers of the sleeve to the shaft.

It will be evident that while I have shown in my drawings an operative device still many changes might be made both in size shape and arrangement of parts witheutdeparting materially from the spirit of my invention and I wish, therefore, that my drawings be regarded as in a sense diagran1- matic.

It will be understood that where I have used the term socket, I mean a hole or aperture or place where the removable bearing sleeve is mounted. That socket may be in a brush, a spindle, a. wheel a bracket or any *other part of a machine and it makes no difference whether the socket and bearing rotate and the shaft is at rest or the shaft til ltti

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testata rotates in a bearing and' socket which are at rest, the result and operation is to all intents and urposes the same.

llt will e noted also that the distance through which the distortion caused by pressure on the outside of the bearing spreads and makes itself felt on the inside is relativel small and if we apply pressure localized by a set screw on the outside of the bearing, it is sufficient to cut away only a small part of the bearing beneath the set -screw to take care of the fibrous distortion and strains and avoid all difficulty.

Obviously localized pressure which would tend to distort the bearing and thus grip the shaft and which must be compensated for by cutting away the inside of the bearing sleeve may be caused by the pressure exerted .by the set screw or by a wedge or rivet or by compressing a split socket or driving the sleeve into a socket a little smaller than it is. This localized pressure may be applied at one single spot, along a broad line parallel with the axis of the sleeve, or on a circular line perpendicular to the axis of the sleeve or any other desired way and no matter where it is applied, l arrange the bearing sleeve on the shaft so that by cutting away some part or by relieving solne part of the sleeve ll prevent this localized pressure from being translated in terms of distortion of the shaft engaging portion of the bearing.

'lhe use and operation of my invention are as follows y The wood or fiber bearings which ordinarily come from the factory in the form of a hollow cylindrical bearing blank maybe turned down on the outside throughout the major part of their length and then bored out from the inside on their end to overlap the reduced part so lthat the bored out part is always longer than the unreduced part of the outside. ln another exemplication the blank may be reduced intermediate its ends on the outside and enlarged intermediate its ends on the inside or it may be left cylindrical on the outside and bored out almost throughout its length on the inside or it may be bored out at each end and reduced intermediate its ends in which case as above indicated depending on the peculiar desires of the designer and the purposes for which the device may be used and the place where it is to` be put.

lin every event, however, no matter how the specific blank is treated the finished bearing blank which has" been prepared is forced into the pocket or socket in the en.- larged end of the brush body or in any other suitablev place where such pocket or socket may be disposed. The inner bearing is then reamed out to size but such size is always less than the diameter of the bored out or increased inner portion of the sleeve. rllhe shaft is then inserted and turns freely with respect to the bearing. Of course, .the ber i or fabric of thematerial ,is placed under serious strains by compression and is more or less distorted when'the sleeve bearing is forced into place and these strains and distortions cause a certain amount of movement and displacement of the fiber of the bearing and this distortion is slightly but-steadily transmitted and felt at theinside of the sleeve, and `would as above indicated lock the sleeve and shaft together were it not for the fact that such distortion is not sufficient to bringthe enlarged or bored out portion of the bearing sleeve in contact with theA shaft and cannot adect the sized portion of the sleeve because the sized portion 4is sufficiently removed from that part of the sleeveV where the pressure is felt.

l. A bearin comprising a socket, a bearing sleeve ttmg within the socket, a shaft in rotatable relation with'the bearing sleeve said sleeve having part of its interior surface out of contact with the shaft and part of its exterior surface out of contact with the socket.

2. A bearing comprising a socket, a bearing sleeve fitting within the socket, a shaft in rotatable relation with the bearing sleeve said sleeve having part of its interior surface out of contact with the shaft and part of its exterior surface out of contact with the socket the two non-contacting surfaces being at opposite ends of the bearing.

3. Abearing comprising a socket, a bearing sleeve fitting within the socket, a shaft in rotatable relation with the bearing sleeve said sleeve having part of its interior surface out of contact with the shaft and part of its exterior surface out of contact with the socket, the interior and exterior non-contacting surfaces being spaced from one another along the axis of the sleeve.

A. A bearing comprising a socket, a bean ing sleeve fitting within the socket, a shaft in rotatable relation with the bearing sleeve said sleeve having part of its interior surface out of contact with the shaft and part of its exterior surface out of contact with the socket the two non-contacting surfaces being at opposite ends of the bearing the interior and exterior non-contacting surfaces being spaced from one another along' the axis of the sleeve.

5. A bearing comprising a socket a hollow bearing sleeve located therein a shaft rotatable within such sleeve the bearing sleeve having a part of its inner surface out of contact with the shaft and a part of its outer surface out of contact with the wall of the socket.

6. A bearing comprising a socket a hollow bearing sleeve located therein a shaft rotatable within such sleeve the bearing sleeve having a part of 'its inner surface out lill llo

outer surface out of contact with the wall ofthe socket the portions of the sleeve which are in contact with the shaft and with the socket being removed from one another in a direction parallel with the axis of rotation of the shaft.

7. A bearing comprising a socket a hollow bearing sleeve located therein a shaft rotatable within such sleeve the sleeve being out of contact with the socket for a art of its length and in contact with the sha throughout that portion of its length where it is out of contact with the socket only.

8. A bearing comprising a socket a hollow bearing sleeve located therein a shaft rotatable Within such sleevethe inside and outside of the sleeve being laid to a plurality of different diameters thesocket engaging the largest diameter of the outside of the sleeve'the shaft engaging the smallest diameter of the inside of the sleeve.

9. A bearing comprising a socket a hollow bearing sleeve located thereina shaft rotatable within such sleeve the'inside and outside of the sleeve being laid to a plurality of [11. The combination with a shaft of a bearing Isleeve rotatable with respect thereto, a socket in which vsuch bearing sleeve is adapted to be contained and means associated 'with said socket for exerting a localized pressure upon the outside of the bearing` surface located within that 'part of the sleeve which is out ofengagement with the socket, the shoulder being of greater interior diameter than the bearing.

13. A. bearing comprising a rigid socket, a bearing sleeve therein having a shoulder at one end, the body of the sleeve being of smaller diameter than the'socket, a bearing surface located within that part of the sleeve which is'out of engagement with the socket,

-the sleeve at its shoulder end being of greater interior diameter than the bearing, the shouldered end of the sleeve being bored out to greater interior -diameter than the bearing portion of the sleeve the increased diameter continuing within the sleeve for a distance not less than the length of the shoulder.

In testimony whereof, I alix my signature in the presence of two witnesses this fifth day of March, 1918.

HOWARD EARL HOOVER.

Witnesses:

MINNIE M. LINDEMAN, MARION L. INGRAHAM. 

